Antenna



FIG. 1 is a top plan view of an antenna, showing our new design;

FIG. 2 is a side elevation view thereof;

FIG. 3 is a front elevation view thereof;

FIG. 4 is a bottom plan view thereof; and,

FIG. 5 is a top perspective view thereof.

The broken line in the figure drawings represents unclaimed environment only and forms no part of the claimed design. 

CLAIM The ornamental design for an antenna, as shown and described. 